Why system UIButton don't animate when it is near Navigation controller space (left)

Question

Why this happened when you click at the button near left side of the View Controller ?

I suspect it is because of presence of Navigation Controller, but I'm not sure.

Could I make button to animate even though I click at this space ?

Answer 1

I suspect this is because of the UINavigationController's interactivePopGestureRecognizer is interfering with the touch events of that button.

Try adding this code in your view controller:

self.navigationController.interactivePopGestureRecognizer.cancelsTouchesInView = NO;      
self.navigationController.interactivePopGestureRecognizer.delaysTouchesBegan = NO;
self.navigationController.interactivePopGestureRecognizer.delaysTouchesEnded = NO;

bluesm's EDIT:

It looks like

self.navigationController.interactivePopGestureRecognizer.delaysTouchesBegan = NO;

is sufficient to bring the "alpha" animation back to the system's UIButtton of iOS 7.